export default {
  namespaced: true,
  
  state: () => ({
    // 购物车的数组,用来存储购物车中每个商品的信息对象
    // 每个商品的信息对象,都包含6个属性
    // { goods_id, goods_name, goods_price, goods_count, goods_small_logo, goods_state }
    cart: JSON.parse(uni.getStorageSync('cart') || '[]')
  }),
  
  mutations: {
    addToCart(state, goods) {
      // 根据goods_id 查询购物车中对应商品 的信息对象
      const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
      // console.log(findResult)
      
      if(!findResult) {
        state.cart.push(goods)
      } else {
        findResult.goods_count += 1
      }
      
      console.log(state.cart)
      
      // 
      this.commit('m_cart/saveToStorage')
    },
    // 将cart购物车数组存储到storage中
    saveToStorage(state) {
      uni.setStorageSync('cart', JSON.stringify(state.cart))
    },
    // 更新购物车种商品的选中状态
    updateGoodsState(state, goods) {
      // 根据goods_id 查询购物车中对应商品 的信息对象
      const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
      // 如果查询到对应的信息对象则执行一下操作
      if(findResult) {
        findResult.goods_state = goods.goods_state
      }
      // 持久化存储到本地
      this.commit('m_cart/saveToStorage')
    },
    // 更新商品的数量
    updateGoodsCount(state, goods) {
      // 根据goods_id 查询购物车中对应商品 的信息对象
      const findResult = state.cart.find(x => x.goods_id === goods.goods_id)
      // 如果查询到对应的信息对象则执行一下操作
      if(findResult) {
        findResult.goods_count = goods.goods_count
        // 持久化存储到本地
        this.commit('m_cart/saveToStorage')
      }
    },
    removeGoodsById(state, goods_id) {
      state.cart = state.cart.filter(x => x.goods_id !== goods_id)
      this.commit('m_cart/saveToStorage')
    },
    updateAllGoodsState(state, newState) {
      // 循环更新购物车中每件商品的goods_state 勾选状态
      state.cart.forEach(x => x.goods_state = newState)
      // 持久化存储到本地
      this.commit('m_cart/saveToStorage')
    },

    
  },
  
  getters: {
    // 购物车中所有商品的总数量
    total(state) {
      // let c = 0
      // state.cart.forEach(goods => c += goods.goods_count)
      // return c
      return state.cart.reduce((total, item) => {
        return total += item.goods_count
      }, 0)
    },
    // 购物车中所有已勾选商品的总数量
    checkedCount(state) {
      return state.cart.filter(x => x.goods_state).reduce((total, item) => {return total += item.goods_count}, 0)
    },
    checkedGoodsAmount(state) {
      return state.cart.filter(x => x.goods_state).reduce((total, item) => {return total += item.goods_count * item.goods_price}, 0).toFixed(2)
    }
  }
  
}